1. Field of the Invention
The present invention relates not only to an apparatus for analyzing levitation phenomenon of a magnetic tape from a rotating magnetic head in a magnetic recording apparatus for use in an audio device, a video device, a computer, etc. but also to the magnetic recording apparatus having a magnetic tape feed mechanism in which the magnetic tape and the magnetic recording head can be held in proper contact with each other at all times.
2. Description of the Prior Art
As shown in FIGS. 2a and 2b, a known magnetic recording apparatus such as a video tape recorder (VTR) and a digital audio tape (DAT) device employing a rotational magnetic head and a flexible magnetic tape includes a rotational drum 11, a fixed drum 12, a magnetic head 14 attached to a head mounting window 17 provided on the rotational drum 11, a magnetic tape 13 and a magnetic tape feed mechanism 16 for feeding the magnetic tape 13. A fluid film of air is produced between the rotational drum 11 rotating at high speed and the magnetic tape 13 so as to levitate the magnetic tape from the rotational drum 11. If amount of levitate of the magnetic tape 13 from the rotational drum 11 is not controlled to about several .mu.m, sufficient magnetic recording properties and interchangeability and feed durability of the magnetic tape 13 cannot be obtained.
Conventionally, in order to control the thickness of the air film and reduce the adhesive friction between the magnetic tape 13 and the drums 11 and 12, the rotational drum 11 and the fixed drum 12 are formed with a number of grooves 15 as shown in FIGS. 2a and 2c.
In the structural design of the magnetic recording apparatus, there is a keen demand for the optimization of the shape and positions of the grooves 15, the shape of the head mounting window 17 and the shape of a sliding face of the magnetic head 14. However, at present, these portions are designed through trial and error based on experimental results. Since reproducibility of the experimental results is not satisfactory, the optimum design of the portions has not been effected so far.
As shown in FIG. 10, an attempt at optimization of the grooves 15 has been made by simulation by a computer. In this computational procedure, structural components of the magnetic recording apparatus including rigid bodies such as the rotational drum 11, the fixed drum 12 and the magnetic head 14 and the magnetic tape 13 subjected to elastic deformation are defined as nodal points and computational solutions for pressures, etc. of fluid in elements such as triangles and quadrangles formed by the nodal points are obtained as shown in FIG. 11. However, in order to express all the many minute structures of the magnetic recording apparatus, for example, the grooves 15, by nodal points and elements and to adapt the minute structures to the simulation by a computer, the computer is required to be provided with a memory having a large storage capacity and the operating time of the computer becomes long. Therefore, practically, it has been so far impossible to calculate the minute structures such as the grooves 15 by the simulation by a computer.